1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a speech recognition apparatus and a method thereof, and more particularly, to a speech recognition apparatus which recognizes a user's speech and a controlling method thereof.
2. Description of the Related Art
Electronic apparatuses having a speech recognition function have been used. Speech recognition is technology which recognizes a user's speech as a voice signal which corresponds to specific words. This technology can be used in various fields. In particular, controlling apparatuses using speech recognition technology is comparatively simple as compared to a related art in which a user needs to press a specific button using the finger or other means, and thus, this technology is widely used for various electronic apparatuses such as a digital television (TV), air-conditioner, home theater as well as personal computer (PC) and mobile communication apparatuses. For example, when a user wishes to watch a program titled ‘ABC,’ a user may input speech by saying ‘turn on ABC,’ a TV recognizes a voice signal of a user through a speech recognition module in the TV, a channel may be changed to a channel broadcasting the ‘ABC’ program.
In a related-art speech recognition technology, in order to rapidly recognize user speech, a lexicon of phonemes of words and a predetermined phoneme generation rule is used to recognize speech. However, there is a problem that new words may be desired to be recognized, and a speech recognition ratio will be reduced for the new words. In particular, it is likely that the newly words are keywords related to current issues or events, and that a user is interested in utilizing the issue keywords. However, the related-art speech recognition technology has a difficulty in that new keywords may only be added to the lexicon one by one, and, accordingly, the speech recognition ratio of new words of the speech recognition apparatus is limited.
Thus, there is a need for automatically learning issue keywords to improve the speech recognition ratio.